Pressure indicator for nuts or bolts



Patented Sept. 2, 1930 y it Q j UNITED STATES PATENT OFFICE Application filed August 2251927. Serial No. 214,625.

The present invention relates to pressure is comparatively thin, it is even possible to indicators for nuts or bolt heads and to combreak the wood member through and this bined indicators and locks for nuts or bolt happens not infrequently. heads. The present device consists of a thin sheet Heretofore in bolting together pieces of metal shown as rectangular in shape with 55 wood or in bolting Wood to metal, in cases its ends 11 bent up at right angles and over where the nut or bolt head is in a counterin the plane of the main portion, the depth sink, the operator, in tightening such nut or of the device being the same as that of the bolt head is unable to tell just when to cease countersinkinwhichit is to be used. Near the 10 turning it in order to obtain suflicient tightcenter is a slotted opening 12 for the passage 0 ening without crushing the wood below it. of a bolt and at one sideof the hole the de- Such crushing quite materially impairs the vice may be out and provided with the prostrength of the wood at this point and in narjecting corners 13 and 14 forming a nut row strips substantially severs the piece. locking device such as is set forth in Patent 15 Among the objects of the invention is to ob- Number 1,617,817 issued February 15, 1927, 65 viate this difficulty and provide means by to the present inventor. by which the operator may gauge the pres lhis device is placed in the countersink as sure and determine the point at which the bolt shown in Fig. 2 in place of the washer F and or nut has reached its maximum tightness when the bolt or screw 15 is tightened serves without materially lessening the strength of to indicate when the wood crushing begins, 70 the wood piece. the indication being the lifting of ends 11 Other objects will readily occur to those toward the full line position of Fig. 2. The skilled in the art upon reference to the folworkman will then easily recognize that furlowing description and accompanying drawther tightening will crush the wood and imings in which I pair the strength thereof. The ends 11 may 25 Fig. lisasection through awood slat showthen be flattened to the dotted line position. ing the'usual bolt and washer and how the As indicated in Fig. 5 the preferred form wood is crushed; of the device is slightly bowed upward as Fig. 2 is a similar section showing the presshown so that when the nut or bolt head cut device; presses down on the part 10, this will flatten 80 Fig. 3 is a plan view of Fig. 2, out and cause the corners 20 to move laterally Fig. l is a perspective view of the indicator; 7 and enter the walls of the countersink, hold- Fig. 5 is a longitudinal section thereing it firmly against any displacement. through. The indicating function of the device does As indicated in the drawings the present not require the use of the locking tongues 13 $5 device is designed chiefly for use with counand 14: but these may be formed and the detersunk wood members and its main purpose vice, then becomcsa nut or bolt locking device is to prevent conditions indicated in Fig. 1. as well as a pressure indicator, the tongues In this figure a slat or other wood member Ais functioning in much the same manner as in bored as at B and countersunk as at G for the the patented device. reception or" a bolt or screw D and its head E, Having now described the invention and a washer F usually being placed under the the preferred form of embodiment thereof it head E. In such constructions, when the is to be understood that the said invention is bolt or screw D is tightened, the workman to be limited, not to the specific details heresorews it down until it admits substantially in set forth but only by the scope of the claims, no further movement, with the result indiwhich follow. cated in this figure, namely, the wood X, un- I claim der the washer becomes crushed and reduces 1. A combined locking device and pressure the thickness of the portion having its full indicator for nuts or bolt heads in counterstrength. If the wood below the countersink sinks in wood members comprising a rectangular strip of thin sheet metal perforated for the reception of a bolt, said strip having its ends bent up at right angles and over into the plane of the main portion and being provided with looking tongues at one side of the perforation.

2. A pressure indicator for nuts or bolt heads in countersinks in Wood members comprising a resilient strip of metal formed to provide a horizontal bolt-receiving base portion, vertical Wing portions, and horizontal end portions, the depth of the Wing portions being substantially the same as the depth of the countersinks, as and for the purpose described.

' EDWARD C. BAYNES. 

